Improvement in preparing roofing-cements



AUNITI-3D STATES Y PATENT OFFICE.

ROBERT T. IIAVENS, OF CASS'IOWN, OHIO.

IMPROVEMENT -|N PREPARING ROOFlNG-OEMENTS.

Specification forming part of Letters Patent No. l 8,278, datedSeptember 29, 1857.

To a/ZZ whom t may concern,.- Y

Be it known that I, ROBERT T. I'IAvENs, of Casstown, in the county ofMiami and State of Ohio, have invented a new and Improved Mode of MakingSlate; and I do hereby declare that the following is a full and exactdescription thereof.

. The nature of my' invention consists in combining coal-tar and sand,sifted through a bolting-cloth or other suitable material, With paperorWood in the following manner: First, I raise the temperature of the tarto a boiling heat and then let it cool, when an oily substance is foundon the top, WhichI skim from the tar. To one gallon of tar thus preparedI add three gallons, or nearly in that proportion, of sand, prepared asaforesaid, and stir them Well together. I then put sheets of paper orvery thin wood in pieces of suitable size into l a rolling-machine whichI have constructed for the purpose and pour the mixture into the hopperof said machine. I then pass the mixture and paper or Wood togetherbet-Ween the rollers of the machine, which is so contrived as to pressthe mixture upon and into the substance of the Wood or paper on bothsides.

In the drawings hereto annexed and made part of this specification,Figure l is a general view of said machine, and Fig. 2 a transversesection of the inside of the hopper thereof.

The hopper is divided into three apartments E, E, and F. The mixtureabove described is poured into the compartments E E and the Wood orpaper placed in F, the three E, E, and F uniting just above the rollersO C, so that at this place'of union the mixture shall come in contactWith the Wood or paper on each side thereof before passing between therollers C C. In turning the rollers the mixture is pressed into thepores of the wood or into the 4paper on each side, making a smoothsurface. The product passes from the press in the direction Irl.

4The draft of this machine is annexed merely to show how by rolling andpressing the mixture is thoroughly and smoothly combined With the Woodor paper. It is not intended thereby to limit the process to the use ofthis or any other particular machine by Which the pressure may beapplied and the smooth surface obtained, my claim not beingl for themere mixture of the coal-tar and sand, nor for the machine, but for theprocess of making artificial slate by combining the mixture abovedescribed With Wood or paperby means of rolling and pressing.

The union thus produced between the mixture and the paper or Wood isextremely close and becomes still closer by time. The composition bymeans of the pressure is forced into the pores of the Wood. 'Ihepaperbeing a more pervious substance, the composition so penetrates itas for all practical purposes to form with it a single body.

I thus produce an artificial slate suitable for marking or rootingpurposes, non-combustible, and which, When exposed to the sun andatmosphere, becomes very hard and exceedingly durable, and which, to thebestof my knowledge and belief, has not been before manufactured orproduced.

I do not claim that the ingredients herein specified have not been usedbefore in compositions, but do claim that theyhave not been so combinedas to produce any article identical with or equivalent or similar to theabove.

Vhat I claim as my invention, and desire to secure by Letters Patent,is-

The process of combining and pressing coal-tar and sand with paper orWood in the manner above described and represented for the production ofan artificial slate.

R. T. IIAVENS.

VWitnesses:

R. S. HEUT, J. O. FELToN.

